It's the ultimate diet dream: you burn more calories eating food than that snack itself contains. That's the idea behind negative-calorie foods, the most famous of which include celery, cucumbers and apples.
Does this magical food really exist? Or like the unicorn, is it merely a myth? Unfortunately, a quick Google search of the term only adds to the confusion.
While, negative-calorie foods do exist in theory, a diet comprised only of these foods is unsustainable, and likely lacking in nutrients.
The Myth, the Legend
When asked if negative-calorie foods exist, Krissy Ruddy, a certified health coach answers with a swift "No."
Here's why: A calorie is simply a unit of energy, Ruddy says. If you burn more energy (calories) than you take in, you will eventually lose weight. Therefore, if you burn 1,600 calories and eat 1,100 calories per day for 7 days you'll lose one pound (3,500 calories total).
The idea behind negative-calorie foods is that you don't have to worry about burning those calories.
"In theory, if you just ate celery, apples, cucumbers and romaine lettuce, and drank water in the right amounts, then you'd lose weight without having to do much else," Ruddy says.
However, eating a wide range of food is necessary to give your body all the nutrients it needs. And a monotonous diet is no fun; variety is what keeps your palette excited.
"I can say from first-hand experience that reducing the connection and pleasure that is available through the enjoyment of food at the sake of saving a few calories is a battle you don't want to win," Ruddy says. The key statement here is: to save a few calories. While negative calorie foods don't exist, low-calorie foods do—but subsiding solely on those can be unexciting and unhealthy.
Instead, she recommends maintaining a fun and healthy diet.
The Negative-Calorie Food Alternatives
Swap out the standard zero-calorie foods with healthier alternatives; your body will thank you. The bonus: You might still drop those unwanted pounds.
Negative-Calorie Queen: Equal and Sweet and Low
Healthier Alternative: Stevia, honey or maple syrup
All of these options are low calorie and provide the sweetness you're craving without the negative effects, which include changing the way you taste foods.
"People who routinely use artificial sweeteners may start to find less intensely sweet foods such as fruit less appealing, and unsweet foods such as vegetables downright unpalatable," says Holly Strawbridge, former editor of Harvard Health.
Not all maple syrup is a good option. Always opt for the real stuff, which lists maple syrup as the main ingredient. Most commercial brands are made with high fructose corn syrup, something you want to steer clear of.
Negative-Calorie Queen: Diet Soda
Healthier Alternative: Sparkling or infused water
Enjoy a bubbly beverage without the harsh sweeteners. Add a lemon wedge, cinnamon stick, sliced apples or strawberries to your still or sparkling water for a tasty beverage that's still low in calories.
Try "Crowding Out"
The good news is that the most popular negative-calorie foods, including celery, cucumber and romaine lettuce, still provide a variety of health benefits. These foods are alkalizing and high in fiber.
The greatest benefit is their ability to help you crowd out the high-calorie, high-fat foods.
"Instead of eliminating all high-calorie foods—aka all the good stuff—and banishing yourself to the mundane world of carrot sticks and lettuce leaves, try bringing fresh, low-calorie veggies into your meals and snacks," Ruddy says.
Some of her favorite recipe suggestions:
Ditch high-calorie tortillas and replace them with Romaine lettuce. Fill lettuce cups or top a pile of cut up lettuce with a mix of your favorite veggies and protein.
Lose the pasta and replace it with low-calorie zucchini noodles, also called zoodles. Make the zoodles heartier with ground turkey, your favorite pasta sauce and broccoli.
The argument for zero-calorie foods isn't unreasonable. But it's not a smart base for your next diet or daily healthy eating habits. You don't have to banish celery and cucumbers altogether. Instead, use them to replace some of your favorite high-calorie foods and mix in other nutrient-dense dishes to let your body reap the benefits.
Stay healthy with our nutrition guide.